The present invention relates to an image reading apparatus suitable for use as a facsimile apparatus, a copying apparatus or the like, and a method for detecting open/close of an original feeding unit in the image reading apparatus.
An image reading apparatus used to read information drawn on an original as image information (including image information or character information) such as a facsimile, an image scanner or the like has been developed in recent years.
In such image reading apparatus, an original set in, for example, a hopper is drawn out one by one and fed on a feeding route so that image information of the original is read on the feeding route.
If a so-called jam that an original jams on the above-mentioned feeding route or the like occurs, the operator opens an openable and closable lid unit constituting an original feeding unit for feeding the original, thereby removing the original jamming on the feeding route.
In the above-mentioned image reading apparatus, lights are radiated on the original fed on the feeding route to read image information on the basis of reflected lights from the original. Therefore, it is necessary to shield disturbing lights from the outside during an image reading operation. The above-mentioned lid unit is also required to be closed since the disturbing lights prevent image information of the original from being appropriately read if the lid unit is in an open state.
In order to prevent the lid unit from being in an open state during the above-mentioned image reading, a general image reading apparatus is provided with an exclusive microswitch served to detect an open/close state of the lid unit so as to notify the open/close state to the operator.
Such general image reading apparatus has, however, a problem that the number of parts increases so as to cause an increase of unnecessary cost required to constitute the apparatus or complicate a structure of the apparatus since the apparatus has an exclusive microswitch to detect the open/close state of the lid unit.